In the usual safety belt mounting structures and in their normal use, the belt is protracted by the user to a position beyond that required when set, the end then clamped, the belt then allowed to retract against the body of the user, exacting pressure on the body of the user, and then be locked against further protraction to secure the user in the seat in the event of sudden change in vehicle movement. The pressure on and excessive confinement of the user, resulting from the use of conventional structures, produce uncomfortable effects needless to his safety.